Numerous prior art attempts have been made to incorporate into an intake manifold unit, as many as possible of the functional components and features required to efficiently produce properly mixed charges of fuel and air and to make these charges readily available to the combustion chambers of an internal combustion engine. In most of the attempts only a limited success was achieved. In some instances integrating the desired components and features into a single assembly, involved intricate, complex or exotic manufacturing procedures which made such units practically impossible to mass produce or too costly to do so. In other instances where the component parts were designed so it was possible to incorporate them into an intake manifold that could be mass produced, the efficiencies of the components were compromised. Accordingly it is a general object of this invention to provide an improved intake manifold assembly which combines a maximum number of related fuel system components, provides for various operating controls, lends itself to mass production techniques and does so without compromising the efficiencies of its functional components.